Mind & Body Behaviourism

Transcription

1 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 1 Mind & Body Behaviourism Cartesian Dualism Duality Mental Cause Parallelism Occasionalism Epiphenomenalism Causal Closure Idealism Double-aspect theory Logical Behaviourism Identity Theory Functionalism

2 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 2 Two different forms of behaviourism I Psychological (methodological) behaviourism states a thesis about empirical psychology. The data for empirical psychology are instances of behaviour, what organisms do (these data are Public instead of Private!). We explain behaviour not by postulating unobservable interior states of mind but by response to environmental stimuli that elicit the behaviour (S-R theories). Philosophical (logical, analytical) behaviourism states a thesis about the meaning of mental terms, ultimately about the nature of mental concepts Assertions concerning states of mind can be translated into statements about behaviour or dispositions to behave. Minds do not exist (We are misled by what Wittgenstein calls the Grammar of our language)

3 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 3 Two different forms of behaviourism II Psychological Behaviourism J. B. Watson, Psychology as the behaviorist views it (1913) B. F. Skinner, Verbal Behavior (1957). All learning can be explained in terms of simple associative mechanisms S-R, including complex tasks such as learning to playing chess and mastering English. Cf. Chomsky s review of Skinner s Verbal Behavior (1959). For Psychological Behaviourists the existence of mental states is possible but irrelevant. Philosophical Behaviourism Carl Hempel, The logical analysis of psychology (1935) Gilbert Reyle, The concept of mind (1949). Mind like brain or baseball is a substantive noun. We reason that mind must designate a kind of entity (similar to shadow, electron and unicorn). However, in order to avoid confusion we should look carefully at the way words are actually used in ordinary circumstances.

4 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 4 Reyle s method of semantic ascent Methodological idea to investigate our ordinary language in which we speak about the phenomenon instead of the phenomenon itself. Investigating the logic of our mentalistic vocabulary by considering certain sentences that express subject s emotions, beliefs, sensations (of pain etc.). Realizing that these sentences have the same conditions of verification as hypothetical statements about the behaviour of organisms. The latter express a content that is publicly observable. Concluding that categorical statements about mental phenomena are semantically equivalent with behavioural dispositions. Therefore, is it not necessary to assume the existence of mental states etc.

5 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 5 Hempel s Example of Toothache Paul has a toothache can given the following behavioural translation: 1. Paul weeps and makes gestures of such and such kind 2. At the question what is the matter? Paul utters the words I have a toothache. 3. Closer examination reveals a decayed tooth with exposed pulp. 4. Paul s blood pressure, digestive processes, the speed of his reaction, show such and such changes. 5. Such and such processes occur in Paul s central nervous system.

6 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 6 Verifiability Principle Verificationism was an important element in the philosophical program of logical positivism (cf. Carl Gustav Hempel, Selected Philosophical Essays, ed. by Richard C. Jeffrey, Cambridge, 2000). The verifiability principle claims that the meaning of a proposition is just the set of observations or experiences which would determine its truth, so that an empirical proposition is meaningful only if it either actually has been verified or could at least in principle be verified. When it became clear that this principle is not very helpful as a methodological principle, the influence of behaviourism went down rapidly.

7 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 7 Difficulties with behavioural translations dispositional properties Substance X is water-soluble S beliefs that p Behavioural conditional If someone puts X in water X will dissolve If S is asked, Is it the case that p? S will answer, Yes, it is the case that p Behavioural conditionals presuppose the truth of additional clauses (The water should be not too cold, there should be no powerful electromagnetic field; S must understand the question, S must want to tell the truth, etc ). In case of mental properties, these extra clauses contain dispositional properties again. Their analysis in terms of behavioural conditionals requires additional dispositional predicates, and so one. This leads to an infinite regress.

8 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 8 Advantages of logical behaviourism It solves Descartes problem by claiming that the mental substances simply do not exist. The role mental terms is simply to indicate a certain behaviour. Creatures possess a mind not in virtue of being equipped with a particular kind of private ingredient, its mind, but in virtue of being the sort of the sort of creature capable of engaging in sufficiently complex behaviour (called intelligent behaviour ). It stresses the relational and functional character of mental states. To have a mind is just to possess a particular sort of organization, one that issues in what we call intelligent behaviour. Highlighting the role of dispositions. An agents is in a certain state of mind not only in virtue what he is actually doing, but also in virtue what he is disposed to do.

9 Blutner/Philosophy of Mind/Mind & Body/Behaviourism 9 Disadvantages of logical behaviourism Behavioural analyses are open-ended. The list of analysis will never end and most of its entries require the introduction of new unanalysed terms (infinite regress). It is unable to account for the causal efficiency of mental states. It crucially makes use of empirism (the assumption that the meaning of sentences can be analysed by its conditions of verification) There is something it is like to have a headache. What it is like to have a headache differs from what is it like to have another kind of conscious experience. To denial this seems implausible.